Mitsubishi Electric JG79A476H01 Installation Manual

1-3. SPECIFICATIONS

Model Power supply *1 Wire specifications *2

Pipe size

(thickness *3, *4)

Indoor unit Outdoor unit Rated Voltage Frequency

Breaker
capacity

Power supply

Indoor/outdoor

connecting wire

Gas / Liquid

MS-GF20VA
MS-GF25VA
MS-GF35VA

MU-GF20VA
MU-GF25VA
MU-GF35VA

230 V 50 Hz 10 A

3-core

2.5 mm

2

4-core

1.0 mm

2

ø9.52 / 6.35 mm

(0.8 mm)

(GF20, 25/GF35)

Pipe length and height difference

Max. pipe length 20/25 m

Max. height difference 10 m

Max. number of bends *5, *6 10

Refrigerant adjustment A *7 20 g/m

Insulation thickness *8, *9

8 mm

1. BEFORE INSTALLATION

1-1. THE FOLLOWING SHOULD ALWAYS BE OBSERVED FOR SAFETY

• Be sure to read “THE FOLLOWING SHOULD ALWAYS BE OBSERVED FOR SAFETY” before installing the air conditioner.

• Be sure to observe the warnings and cautions specified here as they include important items related to safety.

• After reading this manual, be sure to keep it together with the OPERATING INSTRUCTIONS for future reference.

CAUTION

(Could lead to serious injury in particular environments when operated incorrectly.)

WARNING

(Could lead to death, serious injury, etc.)

N Do not install the unit by yourself (user).

Incomplete installation could cause fire, electric shock, injury

due to the unit falling, or leakage of water. Consult the dealer
from whom you purchased the unit or a qualified installer.

N Perform the installation securely referring to the installa-

tion manual.

Incomplete installation could cause fire, electric shock, injury

due to the unit falling, or leakage of water.

N When installing the unit, use appropriate protective equip-

ment and tools for safety.

Failure to do so could cause injury.

N Install the unit securely in a place which can bear the

weight of the unit.

If the installation location cannot bear the weight of the unit,

the unit could fall causing injury.

N Electrical work should be performed by a qualified, expe-

rienced electrician, according to the installation manual.
Be sure to use an exclusive circuit. Do not connect other
electrical appliances to the circuit.

If the capacity of the power circuit is insufficient or there is

incomplete electrical work, it could result in a fire or an electric
shock.

N Earth the unit correctly.

Do not connect the earth to a gas pipe, water pipe, lightning

rod, or telephone earth. Defective earthing could cause electric
shock.

N Do not damage the wires by applying excessive pressure

with parts or screws.

Damaged wires could cause fire or electric shock.

N Be sure to cut off the main power in case of setting up the

indoor P.C. board or wiring works.

Failure to do so could cause electric shock.

N Use the specified wires to connect the indoor and outdoor

units securely and attach the wires firmly to the terminal
block connecting sections so the stress of the wires is
not applied to the sections. Do not extend the wires, or
use intermediate connection.

Incomplete connecting and securing could cause fire.

N Do not install the unit in a place where inflammable gas

may leak.

If gas leaks and accumulates in the area around the unit, it

could cause an explosion.

N Do not use intermediate connection of the power cord or

the extension cord and do not connect many devices to
one AC outlet.

It could cause a fire or an electric shock due to defective con-

tact, defective insulation, exceeding the permissible current,
etc.

N Be sure to use the parts provided or specified parts for

the installation work.

The use of defective parts could cause an injury or leakage

of water due to a fire, an electric shock, the unit falling, etc.

N When plugging the power supply plug into the outlet,

make sure that there is no dust, clogging, or loose parts
in both the outlet and the plug. Make sure that the power
supply plug is pushed completely into the outlet.

If there is dust, clogging, or loose parts on the power supply

plug or the outlet, it could cause electric shock or fire. If loose
parts are found on the power supply plug, replace it.

N Attach the electrical cover to the indoor unit and the

service panel to the outdoor unit securely.

If the electrical cover of the indoor unit and/or the service panel

of the outdoor unit are not attached securely, it could result in
a fire or an electric shock due to dust, water, etc.

N When installing, relocating, or servicing the unit, make

sure that no substance other than the specified refrigerant
(R410A) enters the refrigerant circuit.

Any presence of foreign substance such as air can cause

abnormal pressure rise and may result in explosion or injury.
The use of any refrigerant other than that specified for the
system will cause mechanical failure, system malfunction, or
unit breakdown. In the worst case, this could lead to a serious
impediment to securing product safety.

N Do not discharge the refrigerant into the atmosphere. If

refrigerant leaks during installation, ventilate the room.

If refrigerant comes in contact with a fire, harmful gas could

be generated. Refrigerant leakage may cause suffocation.
Provide ventilation in accordance with EN378-1.

N Check that the refrigerant gas does not leak after instal-

lation has been completed.

If refrigerant gas leaks indoors, and comes into contact with

the flame of a fan heater, space heater, stove, etc., harmful
substances will be generated.

N Use appropriate tools and piping materials for installa-

tion.

The pressure of R410A is 1.6 times more than R22. Not using

appropriate tools or materials and incomplete installation could
cause the pipes to burst or injury.

N When pumping down the refrigerant, stop the compressor

before disconnecting the refrigerant pipes.

If the refrigerant pipes are disconnected while the compressor
is running and the stop valve is open, air could be drawn in
and the pressure in the refrigeration cycle could become ab­normally high. This could cause the pipes to burst or injury.

N When installing the unit, securely connect the refrigerant

pipes before starting the compressor.

If the compressor is started before the refrigerant pipes are
connected and when the stop valve is open, air could be
drawn in and the pressure in the refrigeration cycle could
become abnormally high. This could cause the pipes to burst
or injury.

N Fasten a flare nut with a torque wrench as specified in

this manual.

If fastened too tight, a flare nut may break after a long period

and cause refrigerant leakage.

N The unit shall be installed in accordance with national

wiring regulations.

N Install an earth leakage breaker depending on the instal-

lation place.

If an earth leakage breaker is not installed, it could cause

electric shock.

N Perform the drainage/piping work securely according to

the installation manual.

If there is defect in the drainage/piping work, water could drop

from the unit, soaking and damaging household goods.

N Do not touch the air inlet or the aluminum fins of the

outdoor unit.

This could cause injury.

N Do not install the outdoor unit where small animals may

live.

If small animals enter and touch the electric parts inside the

unit, it could cause a malfunction, smoke emission, or fire.
Also, advise user to keep the area around the unit clean.

1-2. SELECTING THE INSTALLATION LOCATION

INDOOR UNIT

• Where airflow is not blocked.

• Where cool air spreads over the entire room.

• Rigid wall without vibration.

• Where it is not exposed to direct sunshine. Do not expose to
direct sunshine also during the period following unpacking to
before use.

• Where easily drained.

• At a distance 1 m or more away from your TV and radio. Opera­tion of the air conditioner may interfere with radio or TV recep­tion. An amplifier may be required for the affected device.

• In a place as far away as possible from fluorescent and incan­descent lights (so the infrared remote control can operate the
air conditioner normally).

• Where the air filter can be removed and replaced easily.

REMOTE CONTROLLER

• Where it is easy to operate and easily visible.

• Where children cannot touch it.

• Select a position about 1.2 m above the floor and check that
signals from the remote controller are surely received by the
indoor unit from that position (‘beep’ or ‘beep beep’ receiving
tone sounds). After that, attach remote controller holder to a
pillar or wall and install wireless remote controller.

Note:

In rooms where inverter type fluorescent lamps are used, the signal
from the wireless remote controller may not be received.

OUTDOOR UNIT

• Where it is not exposed to strong wind.

• Where airflow is good and dustless.

• Where rain or direct sunlight can be avoided as much as pos­sible.

• Where neighbours are not annoyed by operation sound or hot
air.

• Where rigid wall or support is available to prevent the increase
of operation sound or vibration.

• Where there is no risk of combustible gas leakage.

• When installing the unit at a high level, be sure to secure the
unit legs.

• Where it is at least 3 m away from the antenna of TV set or
radio. Operation of the air conditioner may interfere with radio
or TV reception in areas where reception is weak. An amplifier
may be required for the affected device.

• Install the unit horizontally.

• Please install it in an area not affected by snowfall or blowing
snow. In areas with heavy snow, please install a canopy, a
pedestal and/or some baffle boards.

Note:

It is advisable to make a piping loop near outdoor unit so as to
reduce vibration transmitted from there.

Note:

When operating the air conditioner in low outside temperature,
be sure to follow the instructions described below.

• Never install the outdoor unit in a place where its air inlet/
outlet side may be exposed directly to wind.

• To prevent exposure to wind, install the outdoor unit with its
air inlet side facing the wall.

• To prevent exposure to wind, it is recommended to install a
baffle board on the air outlet side of the outdoor unit.

Avoid the following places for installation where air conditioner
trouble is liable to occur.

• Where flammable gas could leak.

• Where there is much machine oil.

• Where oil is splashed or where the area is filled with oily
smoke (such as cooking areas and factories, in which the
properties of plastic could be changed and damaged).

• Salty places such as the seaside.

• Where sulfide gas is generated such as a hot spring.

• Where there is high-frequency or wireless equipment.

• Where there is emission of high levels of VOCs, including
phthalate compounds, formaldehyde, etc., which may cause
chemical cracking.

*1 Connect to the power switch which has a gap of 3 mm or more

when open to interrupt the source power phase. (When the

power switch is shut off, it must interrupt all phases.)
*2 Use wires in conformity with design 60245 IEC 57.
*3 Never use pipes with thickness less than specified. The pres-

sure resistance will be insufficient.
*4 Use a copper pipe or a copper-alloy seamless pipe.

*5 Be careful not to crush or bend the pipe during pipe bending.
*6 Refrigerant pipe bending radius must be 100 mm or more.
*7 If pipe length exceeds 7.5 m, additional refrigerant (R410A)

charge is required. (No additional charge is required for pipe
length less than 7.5 m.)

Additional refrigerant = A × (pipe length (m) – 7.5)

*8 Insulation material : Heat resisting foam plastic 0.045 specific

gravity

*9 Be sure to use the insulation of specified thickness. Excessive

thickness may cause incorrect installation of the indoor unit and
insufficient thickness may cause dew drippage.

Required Tools for Installation

Phillips screwdriver
Level
Scale
Utility knife or scissors
65 mm hole saw
Torque wrench
Wrench (or spanner)

4 mm hexagonal wrench
Flare tool for R410A
Gauge manifold for R410A
Vacuum pump for R410A
Charge hose for R410A
Pipe cutter with reamer

JG79A476H01

SPLIT-TYPE AIR CONDITIONERS

INSTALLATION MANUAL

ENGLISH

English is

original.

Model names are indicated in 1-3.

(B)

(I)

(K)

(G)

(E)

(C)

(7)

(3)

(4)

(6)

(5)

(D)

(F)

(2)

(1)

(A)

110 mm

or more

100 mm

or more

100 mm

or more

350 mm

or more

100 mm

or more

200 mm

or more

Open two sides of left,
right, or rear side.

1-4. INSTALLATION DIAGRAM

2-1. FIXING OF INSTALLATION PLATE

• Find a structural material (such as a stud) in the wall and fix installation plate (1) hori­zontally by tightening the fixing screws (2) firmly.

• To prevent installation plate (1) from vibrating, be sure to install the fixing screws in the
holes indicated in the illustration. For added support, fixing screws may also be installed
in other holes.

• When bolts recessed in the concrete wall are to be utilized, secure installation plate (1)
using 11 × 20 · 11 × 26 oval hole (450 mm pitch).

• If the recessed bolt is too long, change it for a shorter one available in the market.

2-2. WALL HOLE DRILLING

1) Determine the wall hole position.

2) Drill a ø65 mm hole. The outdoor side should be 5 to 7
mm lower than the indoor side.

3) Insert wall hole sleeve (C).

2-3. CONNECTING WIRES FOR INDOOR UNIT

You can connect indoor/outdoor lead wire without removing the front panel.

1) Open the front panel.

2) Remove VA clamp.

3) Pass indoor/outdoor unit connecting wire (A) from the back of the indoor unit and process
the end of the wire.

4) Loosen terminal screw, and connect first the earth wire, then indoor/outdoor unit con­necting wire (A) to the terminal block. Be careful not to make mis-wiring. Fix the wire to
the terminal block securely so that no part of its core is appeared, and no external force
is conveyed to the connecting section of the terminal block.

5) Firmly tighten the terminal screws to prevent them from loosening. After tightening, pull
the wires lightly to confirm that they do not move.

6) Secure indoor/outdoor unit connecting wire (A) and the earth wire with the VA clamp.
Never fail to hook the left claw of the VA clamp. Attach the VA clamp securely.

ACCESSORIES

Check the following parts before installation.
<Indoor unit>

(1) Installation plate 1

(2)

Installation plate fixing screw
4 × 25 mm

5

(3) Remote controller holder 1

(4)

Fixing screw for (3)

3.5 × 16 mm (Black)

2

(5) Battery (AAA) for (6) 2

(6) Wireless remote controller 1

(7)

Felt tape
(For left or left-rear piping)

1

PARTS TO BE PROVIDED
AT YOUR SITE

(A) Indoor/outdoor unit connecting wire* 1

(B) Extension pipe 1

(C) Wall hole sleeve 1

(D) Wall hole cover 1

(E) Pipe fixing band 2 to 5

(F) Fixing screw for (E) 4 × 20 mm 2 to 5

(G) Piping tape 1

(H) Putty 1

(I)

Drain hose
(or soft PVC hose, 15 mm inner
dia. or hard PVC pipe VP16)

1

(J) Refrigeration oil 1

(K) Power supply cord* 1

Units should be installed by licensed contractor
according to local code requirements.

Liquid pipe

Gas pipe

Felt tape (7)

Indoor/outdoor unit
connecting wire (A)

Piping tape (G)

Indoor unit

Wall hole
sleeve (C)

Cut off the
extra length.

Pipe fixing band
(E)

Be sure to use wall hole
sleeve (C) to prevent in­door/outdoor connecting
wire (A) from contacting
metal parts in the wall
and to prevent damage by
rodents in case the wall
is hollow.

Wall hole cover (D)

Seal the wall hole
gap with putty (H).

Fix the pipe to wall
with pipe fixing
band (E).

Fixing screw (F)

After the leak test, apply
insulating material tightly so
that there is no gap.

When the piping is to be
attached to a wall containing
metals (tin plated) or metal
netting, use a chemically
treated wooden piece 20 mm
or thicker between the wall
and the piping or wrap 7 to 8
turns of insulation vinyl tape
around the piping.
To use existing piping, per­form COOL operation for
30 minutes and pump down
before removing the old air
conditioner. Remake flare
according to the dimension
for new refrigerant.

2. INDOOR UNIT INSTALLATION

2-4. PIPE FORMING AND DRAIN PIPING

Pipe Forming

• Place the drain hose below the refrigerant piping.

• Make sure that the drain hose is not heaved or snaked.

• Do not pull the hose when applying the tape.

• When the drain hose passes the room, be sure to wrap
insulation material (obtainable at a store) around it.

* Note:

Place indoor/outdoor unit connecting wire (A) and
power supply cord (K) at least 1 m away from the
TV antenna wire.

Appearance of the outdoor unit may differ from some models.

100 mm

or more

Air inlet

Air outlet

Outdoor unit installation

4-10 mm × 16 mm slot

718 mm

70 mm

500 mm

300 mm

255 mm

264-280 mm

40 mm

12 mm

or more

54 mm or

more/ 130 mm

or more for left and

left back piping

(using spacer)

Wall

Outdoor
side

5-7 mm

ø65 mm

Installation plate (1)

Plumb

Align the plumb
line with the
mark

.

Center of
ø65 mm hole

110 mm
or more

100 mm
or more

Bind the line to the center hole.

54 mm or more
130 mm or more for left and left
back piping (using spacer)

Ceiling

Wall Wall

Fixing screw (2)

* Same for left hole.

Insert
the
scale. *

Align the
scale with
the line. *

100 mm

Level

Terminal block

Fixing screw

Indoor/outdoor unit
connecting wire (A)

VA clamp

Lead wire

15 mm

35 mm

• For future servicing, give extra length to
the connecting wires.

• Make earth wire a little longer than others.
(More than 60 mm)

• Do not fold the excess wire, or cram it into
small space. Take caution not to damage
the wires.

• Be sure to attach each screw to its corre­spondent terminal when securing the cord
and/or the wire to the terminal block.
Note: Do not place the wires between the
indoor unit and the installation plate (1).
Damaged wire could cause heat genera­tion or fire.

Indoor terminal block

Indoor/outdoor
unit connecting
wire (A)

Outdoor terminal block

Earth wire
(green/yellow)

2NL

2NL